Underpitched yeast

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jt43

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Okay, so after doing a little research I realized that I under pitched my yeast by 130,000,000 cells. The brew is on its second day of fermentation and the airlock is very active. Knowing that I under pitched should I make a starter with the same yeast strand ( wyeast northwest ale) and add it to the fermenter?
 
Edit, I see you put the yeast strain in there, oops. What about the gravity? Ill assume you just pitched one pack into a 5g batch.
 
jt43 said:
Okay, so after doing a little research I realized that I under pitched my yeast by 130,000,000 cells. The brew is on its second day of fermentation and the airlock is very active. Knowing that I under pitched should I make a starter with the same yeast strand ( wyeast northwest ale) and add it to the fermenter?

The cells you pitched already replicated and multiplied during the initial lag phase so really adding more yeast now would be a waste, IMO
 
You have a couple of reasonable options: Get/grow more yeast and pitch it now or let the current yeast work it's way through fermentation, then asses the situation after 2-3 weeks of fermenting. If it were me, I'd wait to see the results then, if the FG is too high, move the beer to a secondary and re-pitch at that time. Many brewers only pitch one pack of liquid yeast and swear by the results...though pitching sufficient yeast cells will almost always make better beer.
 
ktraver97ss said:
Edit, I see you put the yeast strain in there, oops. What about the gravity? Ill assume you just pitched one pack into a 5g batch.

My OG was 1.086 The temp was 68f I pitched two packs of wyeast northwest ale which gave 2 billion yeast cells. They were both smacked threes hours prior being pitched and both pouches swelled like they should. I aerated by pouring the wort back and forth between two sanitized buckets ten times. 7 hours later I started to notice airlock activity.

The FG for this brew is supposed to be 1.010 and my OG was supposed to be 1.072. Don't know why the OG turned out so high.
 
MileHiBrewingSupplies said:
You have a couple of reasonable options: Get/grow more yeast and pitch it now or let the current yeast work it's way through fermentation, then asses the situation after 2-3 weeks of fermenting. If it were me, I'd wait to see the results then, if the FG is too high, move the beer to a secondary and re-pitch at that time. Many brewers only pitch one pack of liquid yeast and swear by the results...though pitching sufficient yeast cells will almost always make better beer.

I think I will wait 4 more days then take a gravity reading and assess then. If I did add more yeast how would the lack of oxygen affect the respiration phase?
 
Since this was a high gravity beer, it's pretty certain that you'll need to pitch more yeast after moving it to a secondary. I'd recommend getting another yeast pack and doing a starter (do you know how to build a starter?). Aerate the starter REALLY well, then pitch at hi-krauesen to your batch. That should provide enough oxygen for the remaining work the new yeast has to do.

Just FYI, big beers like this need a LOT of yeast. One BRAND NEW (just made...) pack of WYEAST contains the POTENTIAL for 100 billion cells. A 1.080 beer needs around 540 billion cells...or 5 new packs. So, it would be a great idea to learn and do a yeast starter!
 
MileHiBrewingSupplies said:
Since this was a high gravity beer, it's pretty certain that you'll need to pitch more yeast after moving it to a secondary. I'd recommend getting another yeast pack and doing a starter (do you know how to build a starter?). Aerate the starter REALLY well, then pitch at hi-krauesen to your batch. That should provide enough oxygen for the remaining work the new yeast has to do.

Just FYI, big beers like this need a LOT of yeast. One BRAND NEW (just made...) pack of WYEAST contains the POTENTIAL for 100 billion cells. A 1.080 beer needs around 540 billion cells...or 5 new packs. So, it would be a great idea to learn and do a yeast starter!

I haven't made a yeast starter yet, but I think I'm going to start from now on. Should I do the standard 2L starter or step it up to 4L?
 
jt43 said:
I haven't made a yeast starter yet, but I think I'm going to start from now on. Should I do the standard 2L starter or step it up to 4L?

Every beer will be different and a lot depends on the freshness of the yeast.

Visit Www.yeastcalc.com and you can plug in numbers for each batch you brew and it will calculate the starter size for you to achieve the proper pitch rate as well as any step ups you might need
 
I'd recommend 4 liters. I have some good starter instructions which I tried to attach for you here but it failed. I'll post a link for you tomorrow. Good luck!
 
If you have good activity after day 2, I'd let it ride, but that is just me. I do IIPAs that hover around 1.080 and I use two packs of S-05 and I've had no problems hitting my FG within my targeted time.

Was it optimal? Dunno, but it made damn good beer. One thing I learned a long long time ago is don't f**k with it if you don't have to. You start second guessing and adding additional steps and changing things up mid swing you are going to have no idea what worked and what didn't.
 
Here are the ingredients for the IPA any ideas why the OG came out so high?
7lbs of light dme
1lb Munich malt
1lb crystal 40l malt
30 HBUs of centennial hops added at 60 min
3 oz Cascade ( plan on dry hopping)
1tsp gypsum
1tsp Irish moss

Steeped the grains in three gallons of water. Once water began to boil removed the grains with a strainer. Added malt extract to wort once a boil started I added centennial hops, gypsum, and boiled for 50 min. At 50 min added Irish moss and continued for 10 min. Removed wort chilled to 68F then added wort to two gallons of water in primary topped of to 5 gallons and aerated. Took a gravity reading then pitched yeast. Sealed it up wit an airlock
 
Its been a long time since I brewed an extract, but I'm not tracking how 7#s of DME can give you an OG over over 1.080 with a 5 gal batch. I'd say you should be sitting around 1.060ish.

EDIT: let her ride, I wouldn't do a thing.
 
Paulgs3 said:
Its been a long time since I brewed an extract, but I'm not tracking how 7#s of DME can give you an OG over over 1.080 with a 5 gal batch. I'd say you should be sitting around 1.060ish.

I know I looked at the hydrometer three times because I didn't believe it either. The only thing i can think of is that LHBS gave more DME then what is called for
 
If it was me in your situation, just let it go. I worked with an awesome phd for years and the greatest thing she ever taught me was: "it is what it is".

Your beer will be fine.
 
I know I looked at the hydrometer three times because I didn't believe it either. The only thing i can think of is that LHBS gave more DME then what is called for

My guess is poor mixture with the top off water, probably gave you an invalid OG. With extract, it's really hard to miss.
 
I agree with gcdowd...often times the water and wort don't mix well when doing partial boils like this. Now that we know you're true gravity is more likely around 1.051, you may well be ok. So sit tight, let your yeast do it's job, and see what you have in 2 to 3 weeks.

Paulgs3: Dry yeast packs have considerably more cells than liquid yeast, so 2 packs of US-05 would be right on for 1.080. 11.5 gram dry yeast packs contain around 200 billion cells, so 2 packs should be pretty close.
 
MileHiBrewingSupplies said:
I agree with gcdowd...often times the water and wort don't mix well when doing partial boils like this. Now that we know you're true gravity is more likely around 1.051, you may well be ok. So sit tight, let your yeast do it's job, and see what you have in 2 to 3 weeks.

Paulgs3: Dry yeast packs have considerably more cells than liquid yeast, so 2 packs of US-05 would be right on for 1.080. 11.5 gram dry yeast packs contain around 200 billion cells, so 2 packs should be pretty close.

I took a gravity reading this morning. SG is 1.024. Calculated the attenuation using the following formula: [(OG-FG)/(OG-1)]*100 and got 72% as my attenuation rate which is maxed out for this yeast strain, according to the wyeast website. There was a nice krausen on the top if the brew. The FG for this brew is supposed to be 1.010 I was thinking of buying the same yeast strain making a starter, racking to a secondary then pitching the starter at high krausen in order to reach my FG.

What do you guys think of this course of action?
 
I think that's a reasonable course of action...after giving the beer 2 to 3 weeks in the primary. You can ferment the secondary warmer than the primary (the beer's character is pretty well set after the first week of fermentation), and I'd shoot for around 70 to encourage fermentation. It may be obvious, but don't aerate the beer at this point...rack gently to the secondary. Aerate the starter VERY well.

Good luck!
 
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